Hitch ball lock

ABSTRACT

A lock assembly for securing a trailer including a hitch ball, a lock housing, a lock washer and a nut. The lock housing is placed over the lock washer and nut to prevent the nut from turning. A threaded portion of the hitch ball is placed through a hole in the lock housing and through the lock washer and nut to secure the hitch ball. When a trailer coupler is locked to the ball portion of the hitch ball, the trailer and hitch ball are secure from theft.

CROSS-REFERENCE TO RELATED APPLICATIONS

This invention claims priority to U.S. Provisional Patent ApplicationSer. No. 60/308,643, filed Jul. 30, 2001.

FIELD OF THE INVENTION

The invention relates to a lock for a trailer hitch ball, and morespecifically to a keyless trailer hitch ball lock.

BACKGROUND OF THE INVENTION

Automobile trailers are connected to the back of vehicles by hooking toa trailer hitch located on a draw bar. The trailer hitch coupler engagesthe trailer hitch ball and a coupler lock is provided to secure thetrailer for towing and preventing the theft of the trailer. The draw baris secured to the vehicle receiver by a draw bar lock. Conventionaltrailer lock assemblies incorporate both a draw bar lock and a couplerlock, but do not provide a means for securing the trailer hitch ball.Since the hitch ball can be removed from engagement with the draw bar, atrailer that is only secured by a conventional trailer lock assembly canbe stolen.

Therefore, it is desirable to provide a lock that can secure a trailerhitch ball to prevent theft. It is further desirable to provide such alock that be economically manufactured.

SUMMARY OF THE INVENTION

A lock assembly for use in combination with conventional trailer locksfor securing a trailer and a lock for securing a hitch ball areprovided. The lock includes a housing portion that secures the threadedportion of the hitch ball and prevents removal of the hitch ball whenthe hitch ball is engaged and locked by a trailer coupler.

In one embodiment, the lock assembly includes a hitch ball, a lock body,a lock washer and a nut. The nut is threaded onto the threaded portionof the hitch ball and the lock body prevents the nut from rotating.

In one embodiment the lock includes a two side members and one cross-barmember that intersects the side members. The cross-bar member has a holefor receiving the threaded member of a hitch ball. The lock furtherincludes a first recess, formed by the side members and the cross-barmember, which receives a portion of a vehicle draw bar. In oneembodiment, the lock includes a second recess, formed the side membersand the cross-bar member, which receives a lock washer. The lock furtherincludes two surfaces which are dimensioned to engage a nut placed onthe end of a threaded member of a hitch ball. The engagement of the nutby the lock surfaces prevents the rotation of the nut and the removal ofthe hitch ball.

BRIEF DESCRIPTION OF THE DRAWINGS

The hitch ball lock of the present invention may be more readilyunderstood by reference to the following drawings. While certainembodiments are shown as illustrative examples of the hitch ball lock,the scope of this application should not be construed as limited tothese illustrative examples.

FIG. 1 is an exploded view of a trailer lock assembly of the presentinvention;

FIG. 2 is a front view of a trailer lock assembly in the lockedposition;

FIG. 3 is a side view of a trailer lock assembly in the locked position;

FIG. 4 is a top view of a trailer lock assembly of the presentinvention;

FIG. 5 illustrates a set of adapters for use with a hitch ball lock;

FIG. 6 is a perspective view of a hitch ball lock and adapters;

FIG. 7 illustrates a trailer lock assembly engaged by a trailer coupler;

FIG. 8 illustrates a hitch ball lock of the present invention; and

FIG. 9 is an alternative embodiment of the trailer lock assembly of thepresent invention;

FIG. 10 is an alternative embodiment of the trailer lock assemblyincorporating an integral treaded member;

FIG. 11 is an alternative embodiment of a trailer hitch ballincorporating a hex drive.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a lock assembly, generally referenced as 10,including a hitch ball lock 20, a hitch ball 30, a lock washer 40 and anut 42. The hitch ball 30 and the hitch ball lock 20 engage one end of avehicle draw bar 46.

The hitch ball lock 20, as best shown in FIG. 8, is preferably a solidone piece metal unit made from extrusion, casting, forging or machiningfrom the solid. Optionally, the hitch ball lock 20 can also be stampedand formed from sheet metal as shown in FIG. 9. The hitch ball lock 20is generally H-shaped with two side members 52 and a cross-bar member54. The side members 52 have an upper portion 56 and a lower portion 58each extending away from the cross-bar member 54. The two upper portions56 of the side members 52 of the hitch ball lock 20, along with the topsurface 60 of the cross-bar member 54, provide a recess 65 for receivingthe vehicle draw bar 46. By sliding or placing the vehicle draw bar 46in the recess 65, the hitch ball lock 20 cannot be rotated. While theupper portions 56 of the side members 52 can be curved to secure thevehicle draw bar 46 within the recess 65, it is preferred that the upperportions 56 are generally straight so that the hitch ball lock 20 can beuniversally used with vehicle draw bars 46 of various thickness. Thelower portions 58 of the side members 52 can be thicker at the bottomand have interlocking surfaces 68 for securing the nut 42. When the nut42 is engaged by interlocking surfaces 68, the nut 42 cannot be rotated,and therefore cannot be removed. In the embodiment shown in FIG. 8, arecess 70 is formed below the cross-bar member 54 to allow placement ofthe lock washer 40. If the hitch ball lock 20 was to be used without alock washer 40 or if the lock washer 40 used was the same or smaller insize than the diameter of the nut 42, recess 70 would not be needed andthe lower portions 58 of the side members 52 could extend downward fromthe cross-bar member 54 with a universal diameter, equivalent to thediameter of the nut 42. Furthermore, as shown in FIG. 10, a slot 71 canbe incorporated into either surface the cross-bar member 54 to house thelock washer 40. While the upper portions 56 and lower portions 58 can bein the same plane, as shown in FIG. 8, the upper portions 56 and lowerportions 58 can be rotated 90 degrees from one another as shown in FIG.9. Optionally, the side members 52 can gripping surfaces 72 to allow foreasier handling of the hitch ball lock 20. The cross-bar member 54 has ahole 74 positioned and dimensioned for receiving the threaded portion 78of the hitch ball 30.

The trailer hitch ball 30 can be a variety of known trailer hitch ballsproviding it includes a ball portion 79 and a threaded portion 78. Theball portion 79 is engaged by the trailer coupler 80 and locked intosuch engagement by a trailer coupler lock (not shown). Preferably, thetrailer hitch ball 30 has at least one drive surface that is notaccessible when the trailer coupler 80 is engaged. In the embodimentshown is FIG. 1, the hitch ball 30 has a set of side wrench flats 82 andan end drive socket 84 with end plug 86 to shield the drive socket fromwater and dirt. When engaged with the trailer coupler 80 both the sidewrench flats 82 and the end drive socket 84 are covered by the trailercoupler 80 thereby preventing the trailer hitch ball 30 from beingunscrewed. In another embodiment, shown in FIG. 11, the hitch ball 30has a hex drive 87 located on the top portion of the ball portion 79.The hex drive 87 can also be fitted with a cap to shield the hex drivefrom water and dirt.

To engage the lock assembly 10, the lock washer 40 is inserted into therecess 70 and the nut 42 is place between the interlocking surfaces 68and both the lock washer 40 and the nut 42 are aligned with hole 74.Hitch ball lock 20 is then positioned by sliding the recess 65 aroundthe vehicle draw bar 46 and aligning the hitch ball lock hole 74 withthe draw bar hole 88. The threaded portion 78 of the hitch ball 30 isplaced through holes 74 and 88 and then driven through nut 42 preferablyusing drive surfaces 82 or 84. When a trailer coupler 80, with a trailercoupler lock, is secured to the ball portion 79 of the hitch ball 30,the trailer hitch ball 30 cannot be removed since the drive surfaces 82and 84 are covered by the trailer coupler 80 and the nut 42 is engagedby the hitch ball lock 20.

As shown in FIGS. 5 and 6, one or more adapters 90 can be used toaccommodate different nut 42 sizes. An adapter 90 can slide into thehitch ball lock 20 under the cross-bar member 54 and the protrudingmembers 92 of the adapter 90 slides into the lock washer recess 70. Eachadapter 90 is formed similar to the bottom portion of the hitch balllock 20, with lower side portions 94, interlocking surfaces 68′ and alock washer recess 70′. As such, additional adapters 90 can be useduntil the distance between the interlocking surfaces 68′ is small enoughthat the tolerance between the interlocking surfaces 68′ and the nut 42prohibits the nut from turning. Each adapter 90 can be secured intoplace by inserting the threaded portion 78 of the hitch ball 30 throughthe hole 96 in the top 97 of each adapter 90.

In another embodiment, the lock washer 40 and nut 42 are replaced by athreaded hole in the bottom of the hitch ball lock 20. This embodimenthas less components than other embodiments, however, it does not takeadvantage of the joint pre-load that the lock washer 40 maintains duringvibration of the lock assembly 10. In order to provide a more positivethread lock, this embodiment may include a thread patch or insert intothe threaded joint. In other embodiment, as show in FIGS. 10A-10C, thenut 42 is replaced by an integral threaded hole 98 and a lock washer 40is placed in a slot 99 in the top surface 60 of the cross-bar member 54.

It should be appreciated that the lock assembly 10 may have differentconfigurations and different designs and that such designs are apart ofthe invention as they are provided for within the scope of the claims.

1. A lock for securing a hitch ball comprising: at least two sidemembers and at least one cross-bar member that intersects said sidemembers and has an aperture for receiving a threaded member of a hitchball; a first recess formed by at least two side members and at leastone cross-bar member, wherein said recess is dimensioned to receive aportion of a vehicle draw bar; and at least two surfaces dimensioned toengage a nut placed an the end of the threaded member of a hitch ball;wherein such engagement prevents rotation of the nut.
 2. The lock ofclaim 1 further comprising a second recess formed by at least two sidemembers and a second surface of at least one cross-bar member.
 3. Thelock of claim 1 further comprising a slot formed on one surface of saidcross-bar member.
 4. The lock of claim 1 further comprising an integralthreaded member formed as part of said lock.
 5. The lock of claim 2further comprising one or more adapters placed within said second recessand having at learn two surfaces fur engaging a nut.
 6. A trailer lockassembly comprising: a hitch ball having a ball portion and a threadedportion; a lock housing with a aperture for receiving the threadedportion of said hitch ball; and a threaded member for receiving thethreaded portion of said hitch ball; wherein said threaded member is atleast partially enclosed by a portion of the lock housing such as toprevent rotation of said threaded member; wherein the bitch ball has aset of wrench flats positioned on the hitch ball such that the drivesurface is not accessible when a trailer coupler is placed over thehitch ball.
 7. The trailer lock assembly of claim 6 further comprisingone or more adapters placed within a second recess and having at leasttwo surfaces for engaging a nut.
 8. The trailer lock assembly of claim6, wherein the lock housing further comprises: at least two side membersand at least one cross-bar member that intersects said side members andcontains a hole for receiving the threaded portion of a hitch ball; afirst recess formed by a least two side members and a first surface ofat least one cross-bar member, wherein said recess is dimensioned toreceive a portion of a vehicle draw bar; a second recess formed by aleast two side members and a second surface of at least one cross-barmember; and at least two surfaces dimensioned to engage a nut placed onthe end of a threaded member of a hitch ball; wherein such engagementprevents the rotation of the nut.
 9. The trailer lock assembly of claim8 further comprising a lock washer, wherein said lock washer is disposedwithin said second recess.
 10. The trailer lock assembly of claim 6,wherein the threaded member for receiving the threaded portion of thehitch ball is a nut.
 11. The trailer lock assembly of claim 6, whereinthe threaded member for receiving the threaded portion of the hitch ballis a threaded member that is integral with the housing.
 12. A trailerlock assembly comprising: (a) a hitch ball having a ball portion, athreaded portion, and at least one drive surface positioned on the hitchball such that the drive surface is not accessible when a trailercoupler is placed over the hitch ball; (b) a look housing comprising:(i) at least two side members and at least one cross-bar member thatintersects said side members and has a hole for receiving a threadedmember of a hitch ball; (ii) a first recess formed by a least two sidemembers and a first surface of at least one cross-bar member, whereinsaid recess is dimensioned to receive a portion of a vehicle draw bar;(iii) a second recess formed by at least two side members and a secondsurface of at least one cross-bar member; and (iv) at least two surfacesdimensioned to engage a nut placed on the end of a threaded member of ahitch ball; wherein such engagement prevents rotation of the nut; and(c) a lock washer disposed within said second recess of said lockhousing; and (d) a nut disposed between two surfaces of said lockhousing.
 13. A trailer lock assembly comprising a hitch ball including aball portion, base portion, and threaded portion, a lock housingincluding a recess, and having at least two surfaces for engaging afirst means for securing said hitch ball, and, one or more adapters thatfit within said recess, wherein said lock housing includes a secondmeans for preventing removal of said first means.